ABSTRACT
Small proteoglycans play key roles in fundamental biological contexts such as providing tensile strength to interstitial connective tissues, regulating the mechanical properties of blood vessels, and the status of mineralized tissue. In addition, they exert profound effects on cellular signaling and modulate the activities of several cytokines. The small proteoglycans belong to the small leucine-rich repeat protein family (SLRRP) and are conspicuous components of the interstitial and peribronchial tissue of the lung. They are of importance during remodeling of the lung in physiological as well as pathophysiological conditions owing to their effects on matrix maintenance and on cell and cytokine activities. Therefore they are deeply involved in disease processes such as inflammation associated with fibrosis, emphysema, or allergy. The following presentation will be limited to the relationship between the structure and function of the proteoglycans of the SLRRP family. It will focus on lung functions under both physiological and pathological conditions. Several excellent reviews concerning these proteoglycans are available (1-3).
